smart-json-diff/lib/diff.js

A modern, compact JSON comparison library with path-aware output and multiple output modes

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.smartJsonDiff = smartJsonDiff;
const utils_1 = require("./utils");
function smartJsonDiff(a, b, options = {}) {
    const { output = 'array', onChange, filterPath, compareArraysByIndex = true, strict = true } = options;
    const results = [];
    function compare(objA, objB, path = '') {
        if (strict ? objA === objB : objA == objB) {
            return;
        }
        if (objA === null || objB === null || objA === undefined || objB === undefined) {
            if (objA !== objB) {
                if (!filterPath || filterPath(path)) {
                    results.push({ path, old: objA, new: objB });
                }
            }
            return;
        }
        if (typeof objA === 'function' || typeof objB === 'function' || typeof objA === 'symbol' || typeof objB === 'symbol') {
            return;
        }
        if (typeof objA !== typeof objB) {
            if (!filterPath || filterPath(path)) {
                results.push({ path, old: objA, new: objB });
            }
            return;
        }
        if ((0, utils_1.isObject)(objA) && (0, utils_1.isObject)(objB)) {
            const allKeys = new Set([...Object.keys(objA), ...Object.keys(objB)]);
            for (const key of allKeys) {
                const newPath = path ? `${path}.${key}` : key;
                compare(objA[key], objB[key], newPath);
            }
        }
        else if (Array.isArray(objA) && Array.isArray(objB)) {
            if (compareArraysByIndex) {
                const maxLength = Math.max(objA.length, objB.length);
                for (let i = 0; i < maxLength; i++) {
                    const newPath = `${path}[${i}]`;
                    compare(objA[i], objB[i], newPath);
                }
            }
        }
        else if (objA !== objB) {
            if (!filterPath || filterPath(path)) {
                results.push({ path, old: objA, new: objB });
            }
        }
    }
    compare(a, b);
    if (output === 'callback' && onChange) {
        results.forEach(({ path, old, new: newVal }) => {
            onChange(path, old, newVal);
        });
        return;
    }
    if (output === 'object') {
        const objectResult = {};
        results.forEach(({ path, old, new: newVal }) => {
            objectResult[path] = { old, new: newVal };
        });
        return objectResult;
    }
    return results;
}